Andreas reported that he was seeing the tdbtorture test fail in some
cases with -EDEADLCK when it wasn't before. Some debugging showed that
deadlock detection was sometimes discovering the caller's lock request
itself in a dependency chain.

While we remove the request from the blocked_lock_hash prior to
reattempting to acquire it, any locks that are blocked on that request
will still be present in the hash and will still have their fl_blocker
pointer set to the current request.

This causes posix_locks_deadlock to find a deadlock dependency chain
when it shouldn't, as a lock request cannot block itself.

We are going to end up waking all of those blocked locks anyway when we
go to reinsert the request back into the blocked_lock_hash, so just do
it prior to checking for deadlocks. This ensures that any lock blocked
on the current request will no longer be part of any blocked request
chain.

URL: https://bugzilla.kernel.org/show_bug.cgi?id=202975


Fixes: 5946c431 ("fs/locks: allow a lock request to block other requests.")
Cc: stable@vger.kernel.org
Reported-by: Andreas Schneider <asn@redhat.com>
Signed-off-by: Neil Brown <neilb@suse.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>

The ext4 fstrim implementation uses the block bitmaps to find free space
that can be discarded.  If we haven't replayed the journal, the bitmaps
will be stale and we absolutely *cannot* use stale metadata to zap the
underlying storage.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

During a read failover, we may end up changing the value of
the pgio_mirror_idx, so make sure that we record the layout
stats before that update.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Specifying a retrans=0 mount parameter to a NFS/TCP mount, is
inadvertently causing the NFS client to rewrite any specified
timeout parameter to the default of 60 seconds.

Fixes: a956beda ("NFS: Allow the mount option retrans=0")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Currently, we are releasing the indirect buffer where we are done with
it in ext4_ind_remove_space(), so we can see the brelse() and
BUFFER_TRACE() everywhere.  It seems fragile and hard to read, and we
may probably forget to release the buffer some day.  This patch cleans
up the code by putting of the code which releases the buffers to the
end of the function.

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

All indirect buffers get by ext4_find_shared() should be released no
mater the branch should be freed or not. But now, we forget to release
the lower depth indirect buffers when removing space from the same
higher depth indirect block. It will lead to buffer leak and futher
more, it may lead to quota information corruption when using old quota,
consider the following case.

 - Create and mount an empty ext4 filesystem without extent and quota
   features,
 - quotacheck and enable the user & group quota,
 - Create some files and write some data to them, and then punch hole
   to some files of them, it may trigger the buffer leak problem
   mentioned above.
 - Disable quota and run quotacheck again, it will create two new
   aquota files and write the checked quota information to them, which
   probably may reuse the freed indirect block(the buffer and page
   cache was not freed) as data block.
 - Enable quota again, it will invoke
   vfs_load_quota_inode()->invalidate_bdev() to try to clean unused
   buffers and pagecache. Unfortunately, because of the buffer of quota
   data block is still referenced, quota code cannot read the up to date
   quota info from the device and lead to quota information corruption.

This problem can be reproduced by xfstests generic/231 on ext3 file
system or ext4 file system without extent and quota features.

This patch fix this problem by releasing the missing indirect buffers,
in ext4_ind_remove_space().

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@kernel.org

On machines where the GART aperture is mapped over physical RAM,
/proc/kcore contains the GART aperture range. Accessing the GART range via
/proc/kcore results in a kernel crash.

vmcore used to have the same issue, until it was fixed with commit
2a3e83c6 ("x86/gart: Exclude GART aperture from vmcore")', leveraging
existing hook infrastructure in vmcore to let /proc/vmcore return zeroes
when attempting to read the aperture region, and so it won't read from the
actual memory.

Apply the same workaround for kcore. First implement the same hook
infrastructure for kcore, then reuse the hook functions introduced in the
previous vmcore fix. Just with some minor adjustment, rename some functions
for more general usage, and simplify the hook infrastructure a bit as there
is no module usage yet.

Suggested-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Kairui Song <kasong@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jiri Bohac <jbohac@suse.cz>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Dave Young <dyoung@redhat.com>
Link: https://lkml.kernel.org/r/20190308030508.13548-1-kasong@redhat.com

To 2.19

Signed-off-by: Steve French <stfrench@microsoft.com>

Workaround problem with Samba responses to SMB3.1.1
null user (guest) mounts.  The server doesn't set the
expected flag in the session setup response so we have
to do a similar check to what is done in smb3_validate_negotiate
where we also check if the user is a null user (but not sec=krb5
since username might not be passed in on mount for Kerberos case).

Note that the commit below tightened the conditions and forced signing
for the SMB2-TreeConnect commands as per MS-SMB2.
However, this should only apply to normal user sessions and not for
cases where there is no user (even if server forgets to set the flag
in the response) since we don't have anything useful to sign with.
This is especially important now that the more secure SMB3.1.1 protocol
is in the default dialect list.

An earlier patch ("cifs: allow guest mounts to work for smb3.11") fixed
the guest mounts to Windows.

    Fixes: 6188f28b ("Tree connect for SMB3.1.1 must be signed for non-encrypted shares")

Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

This patch fixes the following KASAN report:

[  779.044746] BUG: KASAN: slab-out-of-bounds in string+0xab/0x180
[  779.044750] Read of size 1 at addr ffff88814f327968 by task trace-cmd/2812

[  779.044756] CPU: 1 PID: 2812 Comm: trace-cmd Not tainted 5.1.0-rc1+ #62
[  779.044760] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-0-ga698c89-prebuilt.qemu.org 04/01/2014
[  779.044761] Call Trace:
[  779.044769]  dump_stack+0x5b/0x90
[  779.044775]  ? string+0xab/0x180
[  779.044781]  print_address_description+0x6c/0x23c
[  779.044787]  ? string+0xab/0x180
[  779.044792]  ? string+0xab/0x180
[  779.044797]  kasan_report.cold.3+0x1a/0x32
[  779.044803]  ? string+0xab/0x180
[  779.044809]  string+0xab/0x180
[  779.044816]  ? widen_string+0x160/0x160
[  779.044822]  ? vsnprintf+0x5bf/0x7f0
[  779.044829]  vsnprintf+0x4e7/0x7f0
[  779.044836]  ? pointer+0x4a0/0x4a0
[  779.044841]  ? seq_buf_vprintf+0x79/0xc0
[  779.044848]  seq_buf_vprintf+0x62/0xc0
[  779.044855]  trace_seq_printf+0x113/0x210
[  779.044861]  ? trace_seq_puts+0x110/0x110
[  779.044867]  ? trace_raw_output_prep+0xd8/0x110
[  779.044876]  trace_raw_output_smb3_tcon_class+0x9f/0xc0
[  779.044882]  print_trace_line+0x377/0x890
[  779.044888]  ? tracing_buffers_read+0x300/0x300
[  779.044893]  ? ring_buffer_read+0x58/0x70
[  779.044899]  s_show+0x6e/0x140
[  779.044906]  seq_read+0x505/0x6a0
[  779.044913]  vfs_read+0xaf/0x1b0
[  779.044919]  ksys_read+0xa1/0x130
[  779.044925]  ? kernel_write+0xa0/0xa0
[  779.044931]  ? __do_page_fault+0x3d5/0x620
[  779.044938]  do_syscall_64+0x63/0x150
[  779.044944]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  779.044949] RIP: 0033:0x7f62c2c2db31
[ 779.044955] Code: fe ff ff 48 8d 3d 17 9e 09 00 48 83 ec 08 e8 96 02
02 00 66 0f 1f 44 00 00 8b 05 fa fc 2c 00 48 63 ff 85 c0 75 13 31 c0
0f 05 <48> 3d 00 f0 ff ff 77 57 f3 c3 0f 1f 44 00 00 55 53 48 89 d5 48
89
[  779.044958] RSP: 002b:00007ffd6e116678 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[  779.044964] RAX: ffffffffffffffda RBX: 0000560a38be9260 RCX: 00007f62c2c2db31
[  779.044966] RDX: 0000000000002000 RSI: 00007ffd6e116710 RDI: 0000000000000003
[  779.044966] RDX: 0000000000002000 RSI: 00007ffd6e116710 RDI: 0000000000000003
[  779.044969] RBP: 00007f62c2ef5420 R08: 0000000000000000 R09: 0000000000000003
[  779.044972] R10: ffffffffffffffa8 R11: 0000000000000246 R12: 00007ffd6e116710
[  779.044975] R13: 0000000000002000 R14: 0000000000000d68 R15: 0000000000002000

[  779.044981] Allocated by task 1257:
[  779.044987]  __kasan_kmalloc.constprop.5+0xc1/0xd0
[  779.044992]  kmem_cache_alloc+0xad/0x1a0
[  779.044997]  getname_flags+0x6c/0x2a0
[  779.045003]  user_path_at_empty+0x1d/0x40
[  779.045008]  do_faccessat+0x12a/0x330
[  779.045012]  do_syscall_64+0x63/0x150
[  779.045017]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[  779.045019] Freed by task 1257:
[  779.045023]  __kasan_slab_free+0x12e/0x180
[  779.045029]  kmem_cache_free+0x85/0x1b0
[  779.045034]  filename_lookup.part.70+0x176/0x250
[  779.045039]  do_faccessat+0x12a/0x330
[  779.045043]  do_syscall_64+0x63/0x150
[  779.045048]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[  779.045052] The buggy address belongs to the object at ffff88814f326600
which belongs to the cache names_cache of size 4096
[  779.045057] The buggy address is located 872 bytes to the right of
4096-byte region [ffff88814f326600, ffff88814f327600)
[  779.045058] The buggy address belongs to the page:
[  779.045062] page:ffffea00053cc800 count:1 mapcount:0 mapping:ffff88815b191b40 index:0x0 compound_mapcount: 0
[  779.045067] flags: 0x200000000010200(slab|head)
[  779.045075] raw: 0200000000010200 dead000000000100 dead000000000200 ffff88815b191b40
[  779.045081] raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
[  779.045083] page dumped because: kasan: bad access detected

[  779.045085] Memory state around the buggy address:
[  779.045089]  ffff88814f327800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045093]  ffff88814f327880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045097] >ffff88814f327900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045099]                                                           ^
[  779.045103]  ffff88814f327980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045107]  ffff88814f327a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045109] ==================================================================
[  779.045110] Disabling lock debugging due to kernel taint

Correctly assign tree name str for smb3_tcon event.

Signed-off-by: Paulo Alcantara (SUSE) <paulo@paulo.ac>
Signed-off-by: Steve French <stfrench@microsoft.com>

Fix Guest/Anonymous sessions so that they work with SMB 3.11.

The commit noted below tightened the conditions and forced signing for
the SMB2-TreeConnect commands as per MS-SMB2.
However, this should only apply to normal user sessions and not for
Guest/Anonumous sessions.

Fixes: 6188f28b ("Tree connect for SMB3.1.1 must be signed for non-encrypted shares")

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>

It was mapped to EIO which can be confusing when user space
queries for an object GUID for an object for which the server
file system doesn't support (or hasn't saved one).

As Amir Goldstein suggested this is similar to ENOATTR
(equivalently ENODATA in Linux errno definitions) so
changing NT STATUS code mapping for OBJECTID_NOT_FOUND
to ENODATA.

Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Amir Goldstein <amir73il@gmail.com>

dedupe_file_range operations is combiled into remap_file_range.
But it's always skipped for dedupe operations in function
cifs_remap_file_range.

Example to test:
Before this patch:
  # dd if=/dev/zero of=cifs/file bs=1M count=1
  # xfs_io -c "dedupe cifs/file 4k 64k 4k" cifs/file
  XFS_IOC_FILE_EXTENT_SAME: Invalid argument

After this patch:
  # dd if=/dev/zero of=cifs/file bs=1M count=1
  # xfs_io -c "dedupe cifs/file 4k 64k 4k" cifs/file
  XFS_IOC_FILE_EXTENT_SAME: Operation not supported

Influence for xfstests:
generic/091
generic/112
generic/127
generic/263
These tests report this error "do_copy_range:: Invalid
argument" instead of "FIDEDUPERANGE: Invalid argument".
Because there are still two bugs cause these test failed.
https://bugzilla.kernel.org/show_bug.cgi?id=202935
https://bugzilla.kernel.org/show_bug.cgi?id=202785



Signed-off-by: Xiaoli Feng <fengxiaoli0714@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

When sending a rdata, transport may return -EAGAIN. In this case
we should re-obtain credits because the session may have been
reconnected.

Change in v2: adjust_credits before re-sending

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

When sending a wdata, transport may return -EAGAIN. In this case
we should re-obtain credits because the session may have been
reconnected.

Change in v2: adjust_credits before re-sending

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

Back in commit a89ca6f2 ("Btrfs: fix fsync after truncate when
no_holes feature is enabled") I added an assertion that is triggered when
an inline extent is found to assert that the length of the (uncompressed)
data the extent represents is the same as the i_size of the inode, since
that is true most of the time I couldn't find or didn't remembered about
any exception at that time. Later on the assertion was expanded twice to
deal with a case of a compressed inline extent representing a range that
matches the sector size followed by an expanding truncate, and another
case where fallocate can update the i_size of the inode without adding
or updating existing extents (if the fallocate range falls entirely within
the first block of the file). These two expansion/fixes of the assertion
were done by commit 7ed586d0 ("Btrfs: fix assertion on fsync of
regular file when using no-holes feature") and commit 6399fb5a
("Btrfs: fix assertion failure during fsync in no-holes mode").
These however missed the case where an falloc expands the i_size of an
inode to exactly the sector size and inline extent exists, for example:

 $ mkfs.btrfs -f -O no-holes /dev/sdc
 $ mount /dev/sdc /mnt

 $ xfs_io -f -c "pwrite -S 0xab 0 1096" /mnt/foobar
 wrote 1096/1096 bytes at offset 0
 1 KiB, 1 ops; 0.0002 sec (4.448 MiB/sec and 4255.3191 ops/sec)

 $ xfs_io -c "falloc 1096 3000" /mnt/foobar
 $ xfs_io -c "fsync" /mnt/foobar
 Segmentation fault

 $ dmesg
 [701253.602385] assertion failed: len == i_size || (len == fs_info->sectorsize && btrfs_file_extent_compression(leaf, extent) != BTRFS_COMPRESS_NONE) || (len < i_size && i_size < fs_info->sectorsize), file: fs/btrfs/tree-log.c, line: 4727
 [701253.602962] ------------[ cut here ]------------
 [701253.603224] kernel BUG at fs/btrfs/ctree.h:3533!
 [701253.603503] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC PTI
 [701253.603774] CPU: 2 PID: 7192 Comm: xfs_io Tainted: G        W         5.0.0-rc8-btrfs-next-45 #1
 [701253.604054] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
 [701253.604650] RIP: 0010:assfail.constprop.23+0x18/0x1a [btrfs]
 (...)
 [701253.605591] RSP: 0018:ffffbb48c186bc48 EFLAGS: 00010286
 [701253.605914] RAX: 00000000000000de RBX: ffff921d0a7afc08 RCX: 0000000000000000
 [701253.606244] RDX: 0000000000000000 RSI: ffff921d36b16868 RDI: ffff921d36b16868
 [701253.606580] RBP: ffffbb48c186bcf0 R08: 0000000000000000 R09: 0000000000000000
 [701253.606913] R10: 0000000000000003 R11: 0000000000000000 R12: ffff921d05d2de18
 [701253.607247] R13: ffff921d03b54000 R14: 0000000000000448 R15: ffff921d059ecf80
 [701253.607769] FS:  00007f14da906700(0000) GS:ffff921d36b00000(0000) knlGS:0000000000000000
 [701253.608163] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [701253.608516] CR2: 000056087ea9f278 CR3: 00000002268e8001 CR4: 00000000003606e0
 [701253.608880] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 [701253.609250] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 [701253.609608] Call Trace:
 [701253.609994]  btrfs_log_inode+0xdfb/0xe40 [btrfs]
 [701253.610383]  btrfs_log_inode_parent+0x2be/0xa60 [btrfs]
 [701253.610770]  ? do_raw_spin_unlock+0x49/0xc0
 [701253.611150]  btrfs_log_dentry_safe+0x4a/0x70 [btrfs]
 [701253.611537]  btrfs_sync_file+0x3b2/0x440 [btrfs]
 [701253.612010]  ? do_sysinfo+0xb0/0xf0
 [701253.612552]  do_fsync+0x38/0x60
 [701253.612988]  __x64_sys_fsync+0x10/0x20
 [701253.613360]  do_syscall_64+0x60/0x1b0
 [701253.613733]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 [701253.614103] RIP: 0033:0x7f14da4e66d0
 (...)
 [701253.615250] RSP: 002b:00007fffa670fdb8 EFLAGS: 00000246 ORIG_RAX: 000000000000004a
 [701253.615647] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f14da4e66d0
 [701253.616047] RDX: 000056087ea9c260 RSI: 000056087ea9c260 RDI: 0000000000000003
 [701253.616450] RBP: 0000000000000001 R08: 0000000000000020 R09: 0000000000000010
 [701253.616854] R10: 000000000000009b R11: 0000000000000246 R12: 000056087ea9c260
 [701253.617257] R13: 000056087ea9c240 R14: 0000000000000000 R15: 000056087ea9dd10
 (...)
 [701253.619941] ---[ end trace e088d74f132b6da5 ]---

Updating the assertion again to allow for this particular case would result
in a meaningless assertion, plus there is currently no risk of logging
content that would result in any corruption after a log replay if the size
of the data encoded in an inline extent is greater than the inode's i_size
(which is not currently possibe either with or without compression),
therefore just remove the assertion.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Allow the async rpc task for finish and update the open state if needed,
then free the slot. Otherwise, the async rpc unable to decode the reply.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Fixes: ae55e59d ("pnfs: Don't release the sequence slot...")
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

qgroup_rsv_size is calculated as the product of
outstanding_extent * fs_info->nodesize. The product is calculated with
32 bit precision since both variables are defined as u32. Yet
qgroup_rsv_size expects a 64 bit result.

Avoid possible multiplication overflow by casting outstanding_extent to
u64. Such overflow would in the worst case (64K nodesize) require more
than 65536 extents, which is quite large and i'ts not likely that it
would happen in practice.

Fixes-coverity-id: 1435101
Fixes: ff6bc37e ("btrfs: qgroup: Use independent and accurate per inode qgroup rsv")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

If 'cur_level' is 7  then the bound checking at the top of the function
will actually pass. Later on, it's possible to dereference
ds_path->nodes[cur_level+1] which will be an out of bounds.

The correct check will be cur_level >= BTRFS_MAX_LEVEL - 1 .

Fixes-coverty-id: 1440918
Fixes-coverty-id: 1440911
Fixes: ea49f3e7 ("btrfs: qgroup: Introduce function to find all new tree blocks of reloc tree")
CC: stable@vger.kernel.org # 4.20+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

When file handle is embedded inside fanotify_event and usercopy checks
are enabled, we get a warning like:

Bad or missing usercopy whitelist? Kernel memory exposure attempt detected
from SLAB object 'fanotify_event' (offset 40, size 8)!
WARNING: CPU: 1 PID: 7649 at mm/usercopy.c:78 usercopy_warn+0xeb/0x110
mm/usercopy.c:78

Annotate handling in fanotify_event properly to mark copying it to
userspace is fine.

Reported-by:  <syzbot+2c49971e251e36216d1f@syzkaller.appspotmail.com>
Fixes: a8b13aa2 ("fanotify: enable FAN_REPORT_FID init flag")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

If the last NFSv3 unmount from a given host races with a mount from the
same host, we can destroy an nlm_host that is still in use.

Specifically nlmclnt_lookup_host() can increment h_count on
an nlm_host that nlmclnt_release_host() has just successfully called
refcount_dec_and_test() on.
Once nlmclnt_lookup_host() drops the mutex, nlm_destroy_host_lock()
will be called to destroy the nlmclnt which is now in use again.

The cause of the problem is that the dec_and_test happens outside the
locked region.  This is easily fixed by using
refcount_dec_and_mutex_lock().

Fixes: 8ea6ecc8 ("lockd: Create client-side nlm_host cache")
Cc: stable@vger.kernel.org (v2.6.38+)
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Parity page is incorrectly unmapped in finish_parity_scrub(), triggering
a reference counter bug on i386, i.e.:

 [ 157.662401] kernel BUG at mm/highmem.c:349!
 [ 157.666725] invalid opcode: 0000 [#1] SMP PTI

The reason is that kunmap(p_page) was completely left out, so we never
did an unmap for the p_page and the loop unmapping the rbio page was
iterating over the wrong number of stripes: unmapping should be done
with nr_data instead of rbio->real_stripes.

Test case to reproduce the bug:

 - create a raid5 btrfs filesystem:
   # mkfs.btrfs -m raid5 -d raid5 /dev/sdb /dev/sdc /dev/sdd /dev/sde

 - mount it:
   # mount /dev/sdb /mnt

 - run btrfs scrub in a loop:
   # while :; do btrfs scrub start -BR /mnt; done

BugLink: https://bugs.launchpad.net/bugs/1812845


Fixes: 5a6ac9ea ("Btrfs, raid56: support parity scrub on raid56")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Commit 7b587e1a ("NFS: use locks_copy_lock() to copy locks.")
changed the lock copying from memcpy() to the dedicated
locks_copy_lock() function. The latter correctly increments the
nfs4_lock_state.ls_count via nfs4_fl_copy_lock(), however, this refcount
has already been incremented in the nfs4_alloc_{lock,unlock}data().
Kmemleak subsequently reports an unreferenced nfs4_lock_state object as
below (arm64 platform):

unreferenced object 0xffff8000fce0b000 (size 256):
  comm "systemd-sysuser", pid 1608, jiffies 4294892825 (age 32.348s)
  hex dump (first 32 bytes):
    20 57 4c fb 00 80 ff ff 20 57 4c fb 00 80 ff ff   WL..... WL.....
    00 57 4c fb 00 80 ff ff 01 00 00 00 00 00 00 00  .WL.............
  backtrace:
    [<000000000d15010d>] kmem_cache_alloc+0x178/0x208
    [<00000000d7c1d264>] nfs4_set_lock_state+0x124/0x1f0
    [<000000009c867628>] nfs4_proc_lock+0x90/0x478
    [<000000001686bd74>] do_setlk+0x64/0xe8
    [<00000000e01500d4>] nfs_lock+0xe8/0x1f0
    [<000000004f387d8d>] vfs_lock_file+0x18/0x40
    [<00000000656ab79b>] do_lock_file_wait+0x68/0xf8
    [<00000000f17c4a4b>] fcntl_setlk+0x224/0x280
    [<0000000052a242c6>] do_fcntl+0x418/0x730
    [<000000004f47291a>] __arm64_sys_fcntl+0x84/0xd0
    [<00000000d6856e01>] el0_svc_common+0x80/0xf0
    [<000000009c4bd1df>] el0_svc_handler+0x2c/0x80
    [<00000000b1a0d479>] el0_svc+0x8/0xc
    [<0000000056c62a0f>] 0xffffffffffffffff

This patch removes the original refcount_inc(&lsp->ls_count) that was
paired with the memcpy() lock copying.

Fixes: 7b587e1a ("NFS: use locks_copy_lock() to copy locks.")
Cc: <stable@vger.kernel.org> # 5.0.x-
Cc: NeilBrown <neilb@suse.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If bio_iov_iter_get_pages() is called on an iov_iter that is flagged
with NO_REF, then we don't need to add a page reference for the pages
that we add.

Add BIO_NO_PAGE_REF to track this in the bio, so IO completion knows
not to drop a reference to these pages.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

For ITER_BVEC, if we're holding on to kernel pages, the caller
doesn't need to grab a reference to the bvec pages, and drop that
same reference on IO completion. This is essentially safe for any
ITER_BVEC, but some use cases end up reusing pages and uncondtionally
dropping a page reference on completion. And example of that is
sendfile(2), that ends up being a splice_in + splice_out on the
pipe pages.

Add a flag that tells us it's fine to not grab a page reference
to the bvec pages, since that caller knows not to drop a reference
when it's done with the pages.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

I've seen cases where bulk alloc fails, since the bulk alloc API
is all-or-nothing - either we get the number we ask for, or it
returns 0 as number of entries.

If we fail a batch bulk alloc, retry a "normal" kmem_cache_alloc()
and just use that instead of failing with -EAGAIN.

While in there, ensure we use GFP_KERNEL. That was an oversight in
the original code, when we switched away from GFP_ATOMIC.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

Make udf_truncate_extents() properly propagate errors to its callers and
let udf_setsize() handle the error properly as well. This lets userspace
know in case there's some error when truncating blocks.

Signed-off-by: Jan Kara <jack@suse.cz>

When truncate(2) hits IO error when reading indirect extent block the
code just bugs with:

kernel BUG at linux-4.15.0/fs/udf/truncate.c:249!
...

Fix the problem by bailing out cleanly in case of IO error.

CC: stable@vger.kernel.org
Reported-by: jean-luc malet <jeanluc.malet@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Permission checks on current's netns should be done only when
netns are enabled.

Reported-by: Dominik Brodowski <linux@dominikbrodowski.net>
Fixes: 23bf1b6b
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

This is a straight port of Al's fix for the aio poll implementation,
since the io_uring version is heavily based on that. The below
description is almost straight from that patch, just modified to
fit the io_uring situation.

io_poll() has to cope with several unpleasant problems:
	* requests that might stay around indefinitely need to
be made visible for io_cancel(2); that must not be done to
a request already completed, though.
	* in cases when ->poll() has placed us on a waitqueue,
wakeup might have happened (and request completed) before ->poll()
returns.
	* worse, in some early wakeup cases request might end
up re-added into the queue later - we can't treat "woken up and
currently not in the queue" as "it's not going to stick around
indefinitely"
	* ... moreover, ->poll() might have decided not to
put it on any queues to start with, and that needs to be distinguished
from the previous case
	* ->poll() might have tried to put us on more than one queue.
Only the first will succeed for io poll, so we might end up missing
wakeups.  OTOH, we might very well notice that only after the
wakeup hits and request gets completed (all before ->poll() gets
around to the second poll_wait()).  In that case it's too late to
decide that we have an error.

req->woken was an attempt to deal with that.  Unfortunately, it was
broken.  What we need to keep track of is not that wakeup has happened -
the thing might come back after that.  It's that async reference is
already gone and won't come back, so we can't (and needn't) put the
request on the list of cancellables.

The easiest case is "request hadn't been put on any waitqueues"; we
can tell by seeing NULL apt.head, and in that case there won't be
anything async.  We should either complete the request ourselves
(if vfs_poll() reports anything of interest) or return an error.

In all other cases we get exclusion with wakeups by grabbing the
queue lock.

If request is currently on queue and we have something interesting
from vfs_poll(), we can steal it and complete the request ourselves.

If it's on queue and vfs_poll() has not reported anything interesting,
we either put it on the cancellable list, or, if we know that it
hadn't been put on all queues ->poll() wanted it on, we steal it and
return an error.

If it's _not_ on queue, it's either been already dealt with (in which
case we do nothing), or there's io_poll_complete_work() about to be
executed.  In that case we either put it on the cancellable list,
or, if we know it hadn't been put on all queues ->poll() wanted it on,
simulate what cancel would've done.

Fixes: 221c5eb2 ("io_uring: add support for IORING_OP_POLL")
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This isn't a straight port of commit 84c4e1f8 for aio.c, since
io_uring doesn't use files in exactly the same way. But it's pretty
close. See the commit message for that commit.

This essentially fixes a use-after-free with the poll command
handling, but it takes cue from Linus's approach to just simplifying
the file handling. We move the setup of the file into a higher level
location, so the individual commands don't have to deal with it. And
then we release the reference when we free the associated io_kiocb.

Fixes: 221c5eb2 ("io_uring: add support for IORING_OP_POLL")
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We currently use the fact that if ->ki_filp is already set, then we've
done the prep. In preparation for moving the file assignment earlier,
use a separate flag to tell whether the request has been prepped for
IO or not.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

The callers all convert to an integer, and we only return 0/-ERROR
anyway.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

Currently when the file system resize using ext4_resize_fs() fails it
will report into log that "resized filesystem to <requested block
count>".  However this may not be true in the case of failure.  Use the
current block count as returned by ext4_blocks_count() to report the
block count.

Additionally, report a warning that "error occurred during file system
resize"

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Currently in add_new_gdb_meta_bg() there is a missing brelse of gdb_bh
in case ext4_journal_get_write_access() fails.
Additionally kvfree() is missing in the same error path. Fix it by
moving the ext4_journal_get_write_access() before the ext4 sb update as
Ted suggested and release n_group_desc and gdb_bh in case it fails.

Fixes: 61a9c11e ("ext4: add missing brelse() add_new_gdb_meta_bg()'s error path")
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Get rid of the special casing of "normal" requests not having
any references to the io_kiocb. We initialize the ref count to 2,
one for the submission side, and one or the completion side.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

This function is never used from the beginning (and is commented out);
let's remove it.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

When admin calls "reboot -f" - i.e., does a hard system reboot by
directly calling reboot(2) - ext4 filesystem mounted with errors=panic
can panic the system. This happens because the underlying device gets
disabled without unmounting the filesystem and thus some syscall running
in parallel to reboot(2) can result in the filesystem getting IO errors.

This is somewhat surprising to the users so try improve the behavior by
switching to errors=remount-ro behavior when the system is running
reboot(2).

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Ext4 needs to serialize unaligned direct AIO because the zeroing of
partial blocks of two competing unaligned AIOs can result in data
corruption.

However it decides not to serialize if the potentially unaligned aio is
past i_size with the rationale that no pending writes are possible past
i_size. Unfortunately if the i_size is not block aligned and the second
unaligned write lands past i_size, but still into the same block, it has
the potential of corrupting the previous unaligned write to the same
block.

This is (very simplified) reproducer from Frank

    // 41472 = (10 * 4096) + 512
    // 37376 = 41472 - 4096

    ftruncate(fd, 41472);
    io_prep_pwrite(iocbs[0], fd, buf[0], 4096, 37376);
    io_prep_pwrite(iocbs[1], fd, buf[1], 4096, 41472);

    io_submit(io_ctx, 1, &iocbs[1]);
    io_submit(io_ctx, 1, &iocbs[2]);

    io_getevents(io_ctx, 2, 2, events, NULL);

Without this patch the 512B range from 40960 up to the start of the
second unaligned write (41472) is going to be zeroed overwriting the data
written by the first write. This is a data corruption.

00000000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
*
00009200  30 30 30 30 30 30 30 30  30 30 30 30 30 30 30 30
*
0000a000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
*
0000a200  31 31 31 31 31 31 31 31  31 31 31 31 31 31 31 31

With this patch the data corruption is avoided because we will recognize
the unaligned_aio and wait for the unwritten extent conversion.

00000000  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
*
00009200  30 30 30 30 30 30 30 30  30 30 30 30 30 30 30 30
*
0000a200  31 31 31 31 31 31 31 31  31 31 31 31 31 31 31 31
*
0000b200

Reported-by: Frank Sorenson <fsorenso@redhat.com>
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Fixes: e9e3bcec ("ext4: serialize unaligned asynchronous DIO")
Cc: stable@vger.kernel.org

We see the following NULL pointer dereference while running xfstests
generic/475:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
PGD 8000000c84bad067 P4D 8000000c84bad067 PUD c84e62067 PMD 0
Oops: 0000 [#1] SMP PTI
CPU: 7 PID: 9886 Comm: fsstress Kdump: loaded Not tainted 5.0.0-rc8 #10
RIP: 0010:ext4_do_update_inode+0x4ec/0x760
...
Call Trace:
? jbd2_journal_get_write_access+0x42/0x50
? __ext4_journal_get_write_access+0x2c/0x70
? ext4_truncate+0x186/0x3f0
ext4_mark_iloc_dirty+0x61/0x80
ext4_mark_inode_dirty+0x62/0x1b0
ext4_truncate+0x186/0x3f0
? unmap_mapping_pages+0x56/0x100
ext4_setattr+0x817/0x8b0
notify_change+0x1df/0x430
do_truncate+0x5e/0x90
? generic_permission+0x12b/0x1a0

This is triggered because the NULL pointer handle->h_transaction was
dereferenced in function ext4_update_inode_fsync_trans().
I found that the h_transaction was set to NULL in jbd2__journal_restart
but failed to attached to a new transaction while the journal is aborted.

Fix this by checking the handle before updating the inode.

Fixes: b436b9be ("ext4: Wait for proper transaction commit on fsync")
Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: stable@kernel.org